The use of polysiloxanes comprising quaternized nitrogen groups is already long-established, especially in cosmetic applications. They serve there in general, as part of wash-off formulations, as conditioning agents for skin and hair.
Thus, for example, EP0282720 and EP0294642 describe cationic polysiloxanes of this kind, in which the quaternary functions are bonded terminally to the polysiloxane, in cosmetic applications. Such compounds offer advantages in terms of their effect as conditioning agents not only for hair and textiles but also for hard surfaces. The use of such compounds in cosmetic formulations has also been described in EP0530974, EP617607, EP 080714, WO 2001082879 and U.S. Pat. No. 6,207,141.
The use of polysiloxanes per se in coating compositions, such as paints and varnishes, for example, is likewise already long-established and, indeed, widespread. Polysiloxanes are used as defoamers and deaerating agents, as wetting agents and as a lubricity additive. The lubricity additive utility derives from the addition reaction of the polysiloxane with the surface of the coating.
Adding minimal amounts of conventional polysiloxane, however, may lead to defects in the dry coating film, which are known to the skilled person as “craters”. Consequently, in some applications, the use of polysiloxanes is strictly limited or even prohibited. One possible solution to this problem is to bond the polysiloxane covalently directly to the binder, for example polyester or polyether, to produce a copolymer. An example is the Silikopur 8080 product from Evonik.
Another class of polysiloxanes used in aqueous coatings are the aminosiloxanes. Too high a concentration of the aminosiloxane, however, may lead to instability and flocculation of the binder. Incorporating such aminosiloxanes into aqueous coating compositions additionally requires strict compliance with a pH of between 5 and 7.
Another disadvantage of aminosiloxanes is the fact that the amino group catalyses the decomposition of the polysiloxane chain. Short-chain siloxane oligomers are formed, and then are lost through evaporation, and the additive loses its effect.
It is noted that citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention.
It is also noted that in this disclosure and particularly in the claims and/or paragraphs, terms such as “comprises”, “comprised”, “comprising” and the like can have the meaning attributed to it in U.S. Patent law; e.g., they can mean “includes”, “included”, “including”, and the like; and that terms such as “consisting essentially of” and “consists essentially of” have the meaning ascribed to them in U.S. Patent law, e.g., they allow for elements not explicitly recited, but exclude elements that are found in the prior art or that affect a basic or novel characteristic of the invention.
It is further noted that the invention does not intend to encompass within the scope of the invention any previously disclosed product, process of making the product or method of using the product, which meets the written description and enablement requirements of the USPTO (35 U.S.C. 112, first paragraph) or the EPO (Article 83 of the EPC), such that applicant(s) reserve the right to disclaim, and hereby disclose a disclaimer of, any previously described product, method of making the product, or process of using the product.